In trying to comprehend our universe, just how big is big? How far is far? This users guide to the cosmos will bring the incomprehensible down to a human scale such as Venus melting a tank, the density of a black hole compared to 1000 cars in a Coke can, and the comets in the Solar System equated to grains of sugar weighing half a ton.更多《宇宙苍穹》完整免费视频、宇宙苍穹在线高清播放、宇宙苍穹高清免费观看相关欧美综艺资源，请持续关注极品电视!